NullReferenceException at SharpHound3.Tasks.NetSessionTasks.<GetNetSessions>

[hkelley]

After running Sharphound in the same environment for many months, something has changed. We now get this when running a collection against our largest domain:

v4.0.2 and 4.0.3 binaries both exhibit the issue. Verbose logging hasn't yielded any clues.

SharpHound.exe --outputdirectory \Bloodhound\JSON --nozip --CollectionMethod All
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Initializing SharpHound at 17:01 on 2021-10-06
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Resolved Collection Methods: Group, Sessions, LoggedOn, Trusts, ACL, ObjectProps, LocalGroups, SPNTargets, Container
 . .. . 

Status: 11092 objects finished (+252 36.97333)/s -- Using 176 MB RAM
Status: 11101 objects finished (+9 33.63939)/s -- Using 175 MB RAM
Status: 11101 objects finished (+0 30.83611)/s -- Using 175 MB RAM
Status: 11101 objects finished (+0 28.4641)/s -- Using 175 MB RAM
Status: 11101 objects finished (+0 26.43095)/s -- Using 175 MB RAM
Status: 11101 objects finished (+0 24.66889)/s -- Using 175 MB RAM

Unhandled Exception: System.AggregateException: One or more errors occurred. ---> System.AggregateException: One or more errors occurred. ---> System.AggregateException: One or more errors occurred. ---> System.NullReferenceException: Object reference not set to an instance of an object.
   at SharpHound3.Tasks.NetSessionTasks.<GetNetSessions>d__1.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter`1.GetResult()
   at SharpHound3.Tasks.NetSessionTasks.<ProcessNetSessions>d__0.MoveNext()
   --- End of inner exception stack trace ---